Oceanographic vehicle and platform

ABSTRACT

A surface and submersible oceanographic vehicle having an opposed paraboloidal hull configuration suitable for buoy and towing applications and capable of controlled excursions in response to surface vessel commands while under tow.

United States Patent 1 1 Bondon et al. 1 Nov. 27 1973 [5 OCEANOGRAPHIC VEHICLE AND 2,928,367 3/1960 McConnick 114 235 PLATFORM 3,105,453 10/1963 Hayes 114 235.2 ux 3,181,182 5/1965 Delaryelle et a1 9/8 [76] Inventors: Lewis A. Bondon, 90 Yantacaw 3,275,976 9/1966 Farmer 9/8 X Brook Rd., Upper Montclair; Bruce'B. Haselman, 71 Burki PL, Freehold, both of NJ. Primary Examiner-Milton Buchler Assistant Examiner-Charles E. Frankfort [22] Filed 1967 Attr )rn eyHopgood and Calimafde [21] Appl. No.: 659,837

Related U.S. Application Data [63] Continuation of Ser. No. 531,197, March 2, 196 6. ABSTRACT [52] U.S. Cl. 114/16 R, 9/8 R, 114/67 R,

114/235 R A surface and submersible oceanographlc vehicle hav- 51 1111. C1 B63b 35/00 ing an Opposed paraboloidal hull configuration Suit- [58] Field of Search 114/0.5, 16,235, able for buoy and towing applicafims and capable 114/235.2, 230, 206; 9/8 controlled excursions in response to surface vessel commands while under tow.

[56] References Cited UNITED STATES PATENTS 2 Claims, 12 Drawing Figures 2,849,978 9/1958 Durham 114/16 1 Pmmgunnvzv ms 4 V 3.774.564

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INVENTORS. LEW/.5 A BOA/DON BRUCE 8. HASELMAN BY A T TORNE Y5.

PATENTED RUY 27 I975 SHEET 2B? 3 I INVENTORS. LEW/5 A- BONOON BRUCE B. HASELMAN PATENTEDNUVZ? I873 SHEET 3 EF INVENTORS LEW/5 A. BONDON BRUCE B. HASELMAN g A T TORNEKS.

OCEANOGRAPI-IIC VEHICLE AND PLATFORM This application is a continuation of US. Pat. application, Ser. No. 531,197 filed Mar.'2, 1966, now abancloned.

This invention relates to a surface and submersible oceanographic vehicle, and in particular, to one which is primarily dependent upon conventional surface ves' sels for locomotion. This invention likewise relates to a stable oceanographic platform or buoy, moored or free floating, utilizing a similar hull configuration.

It is the object of this invention to provide an unmanned towable vehicle which has the following attributes:

Towable upon or below the ocean surface, primarily the latter, with minimum drag and good stability.

Towable at relatively high velocities without generating adverse turbulence about its body.

Capable of supporting large payloads of instrumentation and control equipment.

Capable of controlled excursions in response to surface vessel commands while under tow- Capable of self-propulsion under remote control with a minimum of required power.

Capable of operation in both the vertical and hori zontal attitude.

It is a further object of this invention to provide a highly stable ocean platform whose profile offers the least resistance to hydrodynamic forces in both the vertical and horizontal attitudes. v

Briefly, the invention is predicated upon the concept of a body whose periphery is in the form of opposed paraboloids of revolution; the paraboloidal axes being coincident, and the convex paraboloidal surfaces facing outwardly. The resultant body has a defined edge at the intersection of the complementary paraboloids. When employed as a vehicle the device is preferably ballasted vertically for optimum tow stability and control, i.e., with the paraboloidal axes horizontal. Self-propulsion may also be provided by jets located on the surface of each paraboloid, the thrust of the jets facing in opposition to the direction of tow. When utilized as a stable platform or buoy (usedinterchangeably), the device may be either vertically or horizontally ballasted, depending upon the application advantages.

The above-mentioned and other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will best be understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings wherein:

FIGS. la, lb and show plan and side elevation views of one embodiment of an oceanographic vehicle configuration according to the invention; and

FIG. 2 is a perspective illustration of inventive vehicles in two phases of use;

FIGS. 3 and 4 illustrate the inventive body, horizontally and vertically ballasted, respectively, employed as a free floating platform;

FIG. 5 illustrates the inventive body employed as a submerged buoy;

FIGS. 60 and 6b illustrate the invention moored for near shore and swift current application; and

FIGS. 7 through 9 illustrate assembly ballasting techniques for free floating embodiments.

The description which follows will be divided for clarity in distinct areas dealing with the invention employed first as a towable vehicle and second as an oceanographic platform. It is to be clearly understood that in either case the profile, except for minor changes, (e.g., fins and coupling attachments), remains the same. In FIGS. la through 1c, the peripheral configuration of an oceanographic vehicle according to the invention may be seen. In the embodiment chosen for illustration, the surface is constituted by four sections,

each section being defined by a paraboloid of revolution or frustrum thereof. A paraboloid of revolution is the threedimensional figure obtained by rotating a parabola about its axis, having the general formula:

X Y [(2 (in rectangular coordinates) where k is a function of the distance of the focus from the apex.

Suffice to say, the greater the focal distance (k) the more oblate is the generated surface. Thus piggyback sections A and A have a smaller focus than frustrums B and B, and would therefore accommodate-a greater volume for the same axial length of arc than would a larger focus paraboloid.

At this juncture, it-bears mentioning that for purposes of clarity it has been chosen to depict the piggyback embodiment in detail, since it is the more difficult to visualize. However, a single pair of opposed paraboloids of revolution may also be employed and for illustrative purposes is shown in the hover phase in FIG. 2. This latter embodiment will also dominate the platform disclosure, infra.

While ballistic shapes, such as missiles, have heretofore been defined by axisymmetric paraboloids and ellipsoids, the former of which is probably the best possible axisymmetric shape for fluid flow, the device according to the invention is novel in the fact that it comprises opposed (rather than axisymmetric) paraboloids normally ballasted to an attitute where the paraboloidal axes are perpendicular to the direction of flow. That is, during the tow phase, the vehicle is ballasted so that it takes an attitude shown in FIG. 2 (search) with a minimum area (similar to that shown in FIG. 1c) exposed to the direction of flow. The edge of the vehicle is relatively sharp in contrast with an equivalent ellipsoidal vehicle, and imposes considerably less drag than one of comparable displacement.

It was found that a 675 pound gross weight vehicle having a diameter of 4 ft., ballasted for neutral buoyancy, and having a pair of opposed paraboloids of revolution (the cross sections of which were defined by the equation Y 58X) exhibited a drag force of 42 lbs.- in sea water with no observable cavitation when vertically oriented and towed at velocity of ten knots, submerged 4 ft. below the water surface.

Because of its unique shape, a novel control system is employed. The main propulsion is, as mentioned, by towing, the force of which is transferred via umbilical cables 10 and 12. These cables constitute the only hull penetrations and accordingly enter the vehicle through pressure-type connectors.

During the tow mode of operation, the vehicle is maneuvered from side to side by means of flaperon control surfaces 20, 22, 20' and 22, each of which is preferably flush mounted. The flaperons are activated by a shipboard consol operator who receives an indication of the vehicles depth, attitude and heading on his display consol as transmitted to it via the umbilical cable from the vehicle. Visual displays may also be afforded by side-mounted TV cameras 1 and 2 which view through the plexiglass parabolic domes 11 and 13, and

transmit the pictures via a wide-band transmission cable within the umbilical cable.

At this juncture, it bears mentioning that power to the vehicle may be supplied by two sources. Small vehicles which would operate at depths above 200 ft. would contain batteries and/or receive energy through the umbilical cable from the surface vessel. Large vehicles capable of greater depth penetration must compensate for caternary cable drag. Further, since more instrumentation would probably be included, a supply of energy from the surface vessel would probably be a necessity. If the instrumentation is limited, it is anticipated that larger vehicles would be capable of operating with self-contained batteries.

The umbilical control cable would be constructed for neutral buoyancy, thus only its drag factor need be considered. Cable fairing would only be essential when the mission requires a towing speed in excess of five knots.

The vehicles dynamic stability while being towed is achieved by the yaw stabilizing fins 31 and 33 and the four pitch stabilizing fins 32, 34, 36 and 38. The vehicle is slightly dynamically unstable when motivated under its own power as a result of the design criteria for stabil ity while being towed. However, since the cruise velocity under the vehicles own power would not exceed five knots, the small magnitude of negative dynamic stability can be held in check by the vehicles control system. The small margin of negative stability allows for high vehicle response to commands at low velocity and requires a minimum of control power. In addition, the umbilical tow cable drag would be a stabilizing factor.

As mentioned, an operator aboard the towing vessel may monitor its operation at all times and therefore has full control during all phases of operation. The two plexiglass domes housing the TV cameras permit a 360 field of view which may be supplemented by photographic cameras disposed behind the glass port viewing areas 18. These additional glass areas may also be employed to house flood lights.

Laterally controlled excursions (from side to side) while being towed are possible with the flaperon controls. Large areas may thus be swept while the surface vessel holds a given course. The vertical search attitude of the vehicle allows the cameras and/or audio equipment to view from both sides simultaneously along the tow track. The flaperon control surfaces make rapid changes in vehicle attitude possible without the need of retrimming under all speeds of operation. Vehicle attitude may be maintained in any state by trimming with a movable dry or wet ballast system.

It is a feature of this invention that the vehicle is towed backwards relative to its own propulsion system. This arrangement permits maximum control maneuverability while being towed at high speeds, and conversely at low speeds under its own propulsion in the opposite direction. In the latter phase of operation, additional cable is played out by the surface vessel and propulsion jets 42, 44, 44' and 42' (the latter not being shown) and flaperons 41,41, 43 and 43 are utilized for maneuverability. Intake for these jets are shown at 47, 49, 47' and 49' As before, the consol control, afforded via the umbilical cable, allows remote steering.

' The hovering attitude, shown in FIG. 2, is accomplished by shifting the trim ballast (as mentioned) and exercising control via bang bang hydrojets 51, 52, 53, 51, 52' and 53'.

By utilizing the design principle of two paired paraboloids of revolution, as shown in FIGS. la through Is, a low drag vehicle can be realized with the added capacity of housing a large payload of data collecting instrumentation. The symmetry of this simple form lends itself to added high maneuverability features. The power required to propel an oceanographicvehicle according to the invention is likewise considerably less than that which will be required for other conventional submersible designs of equivalent volume. The slim, compact configuration permits easy shipboard handling, storage, maintenance and launching without the attendant disadvantages of injuring propulsion or maneuvering control systems. Additionally, while being towed, since the vehicle according to the invention is towed in the vertical attitude, it presents its most formidable edge to any bottom obstructions and thus mini mizes the chance of damage. Added protection against bottom damage may be easily accomplished by a bumper rim extension at the joint of the tow paraboloids.

The unique shape of the oceanographic vehicle allows a novel control system to be designed and incorporated. None of the controls, with the exception of the stabilizing fins, protrude beyond the surface of the hull. All controls are positive in response and create a system which is economically feasible and efficient. An equivalent control system as applied to an ellipsoid would be large and cumbersome, as well as being vulnerable to damage during the handling and operation. Sections of a spheroid, on the other hand, would be unfeasible in volumetric requirements.

Further, the unique configuration of the vehicle according to the invention minimizes the possibility of fouling with submerged objects during inspection in turbid waters. However, should this occur, full reverse capability without turning around should offer the vehicle its freedom. This feature makes the inspection of underwater caves, shelves and shipwreck interiors, possible.

The foregoing attributes of the vehicle also yield equally great advantage when the described shape is embodied in an oceanographic platform or buoy. In FIG. 3, a free floating platform is shown. The body is simply and easily horizontally ballasted by, for example, confined water, lead, silicon rubber or the included instrumentation, batteries or powersupply (or the arrangements to be described with reference to FIGS. 7 through 9) to a depth dependent upon the action sought. It is to be noted that -due to the hull configuration the ballast will assume the desired functional position at the lowermost portion of the body. If, for example, it is desired that a surface platform be influenced by ocean currents, it is heavily ballasted. If, on the other hand, it is to follow the wind, it is lightly ballasted. I

In FIG. 3, represents an antenna for radiating or transponding data from the enclosed instrument package. It has been found that by utilizing the disclosed opposed paraboloids as an antenna platform, minimal angular antenna displacement is observed and consequently signal fading from this cause is minimized.

In FIG. 4, the antenna 60 is end-mounted perpendicular to the paraboloidal axes. The body is vertically ballasted and oriented. While it might appear that this orientation would result in considerable antenna displacement (particularly where wind or ocean currents acted along the paraboloidal axis) the opposite is true since the body has a natural tendency to assume an orientation of least resistance. That is, with the paraboloidal axis perpendicular to the fluid flow.

Of particular interest in the deep water mooring of buoys or platforms is the motion of the system as a function of ocean perturbations. The ocean currents continually change in velocity (speed and direction) and therefore a moored system must adjust its attitude and position to achieve equilibrium. This adjustment is known as the mooring motion.

As mentioned, the profile of the inventive body orients itself to a minimum cross-section when exposed to a flowing fluid. This is extremely important in taut line buoy moorings, such as shown in FIG. 5, where a small watch circle radius R is desired. It has been found that the body according to the invention reduces the watch circle radius of conventional configurations by as much as 40 percent.

FIGS. 6a and 6b illustrate end and side views, respectively, of a platform moored near shore where swift wind, wave and water currents are encountered. From the figure, it may be seen that by employing a mooring bridle, which is pivotally affixed at points 71 and 72 on the paraboloidal faces, in conjunction with vertical ballasting, the antenna 74 remains vertically oriented, regardless of the catenary 75. Where quicker response to ocean current velocity changes is desired, a vertical fin (as shown in FIGS. 4 and 6b) may be added, emanating from an edge of the body where the opposed paraboloids meet. It may be noted that WL designates the water line in the absence of current at low tide.

FIG. 7 illustrates a more sophisticated arrangement for still further increased stability. In this case, an underslung similarly shaped weight 80 is suspended from the platform by three cables 81-83. The effective remoteness of the ballast increases the inertia and hence the stability. The horizontal attitude of this ballast weight further acts effectively in damping the buoys response to wave motion.

FIGS. 8 and 9 illustrate alternative ballasting techniques which may be incorporated in, for example, the free floating embodiments of FIGS. 3 and 4. Because of the unique configuration of the ballast, stabilization may be obtained by the simple expediency of increasing the wall thickness of the portion of the body to be submerged. This arrangement utilizes very little of the interior spacing, thereby aiding materially in the payload volume remaining for instrumentation.

While we have described above the principles of our invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of our invention as set forth in the objects thereof and in the accompanying claims, for example, opposed sections of spheres may also be used where their profile approximates the paraboloidal shape.

What is claimed is:

1. A submersible vehicle for tow and control from a surface vessel comprising an umbilical cable coupled to said surface vessel and at least two similar opposed paraboloids of revolution sealed at the line formed by their joining, said opposed paraboloids including two pairs of piggy-back paraboloids of revolution.

2. An oceanographic body for use on moored or free floating systems as a stable platform comprising at least two similar opposed sealed paraboloids of revolution normally ballasted with the paraboloidal axes oriented in a vertical plane, said platform further comprising pivotal means coupled to at least one paraboloidal face for mooring said platform, the paraboloidal axes being horizontally oriented and said pivotal means comprising a V-shaped member coupled to opposing paraboloidal faces edgewise removed from the center of gravity of said platform. 

1. A submersible vehicle for tow and control from a surface vessel comprising an umbilical cable coupled to said surface vessel and at least two similar opposed paraboloids of revolution sealed at the line formed by their joining, said opposed paraboloids including two pairs of piggy-back paraboloids of revolution.
 2. An oceanographic body for use on moored or free floating systems as a stable platform comprising at least two similar opposed sealed paraboloids of revolution normally ballasted with the paraboloidal axes oriented in a vertical plane, said platform further comprising pivotal means coupled to at least one paraboloidal face for mooring said platform, the paraboloidal axes being horizontally oriented and said pivotal means comprising a V-shaped member coupled to opposing paraboloidal faces edgewise removed from the center of gravity of said platform. 